Nov 4, 2016Calculating energy needs for athletes
Athletes must consume enough energy, or calories, on a daily basis to meet their weight and body composition goals, whether it’s to maintain weight, lose weight or gain weight. To maintain energy balance, the intake of solid food, liquids, and supplemental products must equal the energy expenditure.
Without adequate energy intake, training is compromised and athletes are unable to meet their physical and performance goals. Loss of lean tissue can result, which can lead to hampered performance, often related to the loss of lean muscle mass or a decrease in endurance or power.
On the other hand, taking in too many calories can deter an athlete from reaching his or her body composition and performance goals. Extra calories form as fat in our bodies, and in most sports, an athlete’s performance is enhanced with a body composition of primarily lean muscle and a low percentage of fat. Carrying around extra fat pounds will slow an athlete down.
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There are several methods for calculating energy needs. A simple method is to take the athlete’s weight (in pounds) multiplied by 10 for a rough average of basal needs, or basic needs without any exercise. Then, add in an activity factor and an average of calories burned for every minute of exercise. This is a very simplified way to get an initial calculation, from which to fine tune more specifically, but it gives a starting place.
With a 220-pound athlete, calculate basal needs by multiplying the athlete’s weight x 10: 220 x 10 = 2,200 calories
For basic activity, multiply the calories by 20% to 30% and add it to the total:
2,200 x 1.2 – 1.3 = 2,640 – 2,860 calories
Finally, to add exercise calories, add 100 calories for every 10 minutes of hard exercise or a workout. In this example, if the athlete trains hard for three hours on an average day (including sport-specific training and lifting/cross-training), an additional 1,800 calories.
Total calorie needs = 2,640 – 2,860 calories + 1,800 calories = an average of 4,400 – 4,660 calories per day
For a more detailed way to calculate energy needs, another option is to use the calculation below. As you can see, the end results are similar:
Calculate your basal metabolic rate (BMR), the minimal number of calories your body needs just for daily survival. Use this formula:
BMR = 66 + (6.23 x weight in pounds) + (12.7 x height in inches) – (6.8 x age in years)
Example: If you weigh 220 pounds, you’re 6′ tall, and 20 years old, your calculations would look like this:
BMR = 66 + (6.23 x 220) + (12.7 x 72) — (6.8 x 20). That’s 2214 calories per day.
Calculate your Energy Expended for Physical Activity (EEPA), which is all the calories you expend in a day. You can figure this out with this formula:
EEPA = BMR x Activity Level
Activity Level Factors:
- 1.200 = sedentary (little or no exercise due to injury or illness)
- 1.375 = lightly active (about 30 minutes training, moderate 1 to 3 days/week)
- 1.550 = moderately active (moderate 45 minutes, 3 to 5 days/week)
- 1.725 = very active (1 hour, 6 to 7 days a week)
- 1.900+ = extra active (very hard training including weight lifting 2-3 days/week)
Most athletes are between 1.550 and 1.9, depending on the their training. For athletes training at very high levels (3 hours or more per day), calorie needs may exceed recommendations.
Your EEPA based on 220 pounds and hard training is:
2214 x 1.9 = 4206 calories for BMR and EEPA.
Calculate your Specific Dynamic Action of Food (SDA) by multiplying the total of BMR and EEPA in step two by 10%.
Example: Your SDA equals 4206 x 0.1 = 420 calories
Add the total from step two to the total from step 3 to get the overall number of calories you need daily to maintain your present weight.
Total Calorie Needs: 4206 + 420 = 4626 calories